2. The Christopher Morel conundrum
Ideally, the Cubs would send Christopher Morel to the Padres to headline a Soto deal because he is their most tradable player. The only way Soto fits into the Cubs lineup is as the DH because the corner outfield spots are filled by Ian Happ and Seiya Suzuki respectively. Both of those guys are arguably better at playing defense than Soto and the Padres wouldn't want them anyway because they make too much money. The whole point of San Diego moving Soto is to shed money off their inflated payroll so taking on $20 million from a Happ or Suzuki contract wouldn't make sense.
That means the Cubs will have to send prospects and clear up the designated hitter spot, which is currently filled by Morel. The team is so unwilling to teach Morel how to play third base that they instead taught Nick Madrigal to do it and stuck the 24-year-old Morel at DH. But do the Padres want Morel?
Morel's best position is second base and the Padres currently have Ha-Seong Kim at that position, who was at times their best hitter last year, so they would also have to utilize Morel as a DH. That's a hard sell because it limits your lineup possibilities if you need to have Morel as the DH every day just to maximize his value.